The present invention relates to a precision fine powder dispersing supply apparatus, and more particularly, for example, to a precision fine powder dispersing supply apparatus capable of stably supplying a lubricant to a tablet making machine in a dispersed state in a very minute amount which is not substantially varied with time or the variation of which with time is strictly suppressed.
Hitherto, apparatuses for stably supplying inorganic and organic powder having a very small particle size such as metal, ceramic, plastic and the like in a very minute amount in a state that the variation with time of an amount of it to be supplied is very strictly suppressed in respective technical fields of, for example, plasma thermal spraying, spacer spraying apparatuses for liquid crystal substrates, powder compression and formation, sand blast apparatuses, powder coating and the like.
In relation to this field of technology, the apparatus proposed by the applicant in Japanese Unexamined Patent Application Publication No. 5-238544 titled xe2x80x9cPowder Supply Apparatusxe2x80x9d also is widely used.
Incidentally, the above apparatus has a very excellent capability in that it can stably supply fine powder in a dispersed state in a very minute amount while very strictly suppressing the variation with time or the secular variation of the amount of it to be supplied. However, in the apparatus, it is not taken into consideration to use it continuously. Thus, the development of an improved powder supply apparatus capable of fitting this need requirement has not been realized.
An object of the present invention, which was made in view of the above circumstances, is to provide a precision fine powder dispersing supply apparatus having enhanced reliability by more improving the conventionally used powder supply apparatus filed previously such that powder, in particular, fine powder, which is very liable to be deposited on the wall of a vessel, a feed piping system, and the like, can be supplied smoothly for a long period of time in a precisely dispersed state with an additional function of checking how the powder to be supplied is fed or discharged.
In order to attain the object described above, the present invention provides a precision fine powder dispersing supply apparatus for supplying fine powder to a subsequent process in a dispersed state comprising a fine powder storage vessel, a minute amount supply feeder, a supply device for supplying fine powder in the storage vessel to the minute amount supply feeder, and a discharging device for discharging the fine powder from the minute amount supply feeder to the subsequent process.
It is preferable that the minute amount supply feeder comprises a rotary body having at least one circumferential groove which is filled with the fine powder and formed on an outer circumferential surface, at least one thin pipe disposed so that the opening thereof faces the at least one circumferential groove with a predetermined interval defined therebetween, at least one filling device for forcing and filling the fine powder into the at least one circumferential groove of the rotary body and a pressure difference generating device for generating a pressure difference for causing an air flow from a space in which the rotary body is disposed into the at least one thin pipe so that the fine powder that is forced into and filled in the at least one circumferential groove of the rotary body is discharged together with air.
It is also preferable that the pressure difference generating device is a pressurizing device for pressurizing the space in which the rotary body is disposed.
It is another preferable that the minute amount supply feeder includes fine powder presence sensing device disposed in front of and behind the at least one thin pipe to confirm whether or not the fine powder that is forced into and filled in the at least one circumferential groove of the rotary body exists therein and whether or not the fine powder is discharged therefrom.
It is further preferable that valves are disposed to respective ones of an exhaust path from an upper space of the storage vessel, a pressurized air supply path of the pressurizing device and the fine powder discharge path of the fine powder supply feeder as well as a control device is provided to open and close the valves when the apparatus is started and stopped.
It is still another preferable that a heat device is disposed in a transportation path of the fine powder from the fine powder supply feeder to the subsequent process.
It is still further preferable that at least the minute amount supply feeder is placed on a weigher so that a flow rate of the supplied fine powder can be continuously measured.
It is also further preferable that a plurality of circumferential grooves for filling the fine powder are formed as the at least one circumferential groove on the outer circumferential surface of the rotary body as well as a plurality of filling devices for forcing and filling the fine powder into the plurality of circumferential grooves and plurarilty of thin pipes having openings that face the plurality of circumferential grooves with a predetermined interval defined therebetween are disposed as the at least one filling device and the at least one thin pipe in correspondence to the plurality of circumferential grooves and a plurality of outlets of the plurality of thin pipes are disposed so as to correspond to a plurality of the subsequent processes.